target/linux/mediatek/patches/0017-thermal-Allow-sensor-ops-to-fail-with-ENOSYS.patch

   1 From 5b622cb2d6ff44b1fb0750beee61f93f2c00548a Mon Sep 17 00:00:00 2001
   2 From: Sascha Hauer <s.hauer@pengutronix.de>
   3 Date: Wed, 13 May 2015 10:52:36 +0200
   4 Subject: [PATCH 17/76] thermal: Allow sensor ops to fail with -ENOSYS
   5
   6 The thermal core uses the existence of the .get_temp, .get_trend and
   7 .set_emul_temp to detect whether this operation exists and should be
   8 used or whether it should be emulated in software. This makes problems
   9 for of-thermal which has to modify the struct thermal_zone_device_ops
  10 during runtime whenever a sensor is registered or unregistered.
  11
  12 Let the core test for -ENOSYS from these callbacks and treat it like
  13 if the callbacks were not present.
  14
  15 This allows of-thermal to always set the sensor related callbacks and
  16 to make struct thermal_zone_device_ops const again.
  17
  18 Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
  19 ---
  20  drivers/thermal/thermal_core.c |   24 +++++++++++++++++-------
  21  1 file changed, 17 insertions(+), 7 deletions(-)
  22
  23 diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
  24 index 19da022..3d8f9f9 100644
  25 --- a/drivers/thermal/thermal_core.c
  26 +++ b/drivers/thermal/thermal_core.c
  27 @@ -413,13 +413,16 @@ static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
  28   */
  29  int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp)
  30  {
  31 -       int ret = -EINVAL;
  32 +       int ret;
  33         int count;
  34         int crit_temp = INT_MAX;
  35         enum thermal_trip_type type;
  36
  37 -       if (!tz || IS_ERR(tz) || !tz->ops->get_temp)
  38 -               goto exit;
  39 +       if (!tz || IS_ERR(tz))
  40 +               return -EINVAL;
  41 +
  42 +       if (!tz->ops->get_temp)
  43 +               return -ENOSYS;
  44
  45         mutex_lock(&tz->lock);
  46
  47 @@ -445,7 +448,7 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp)
  48         }
  49
  50         mutex_unlock(&tz->lock);
  51 -exit:
  52 +
  53         return ret;
  54  }
  55  EXPORT_SYMBOL_GPL(thermal_zone_get_temp);
  56 @@ -454,10 +457,11 @@ void thermal_zone_device_update(struct thermal_zone_device *tz)
  57  {
  58         int temp, ret, count;
  59
  60 -       if (!tz->ops->get_temp)
  61 +       ret = thermal_zone_get_temp(tz, &temp);
  62 +
  63 +       if (ret == -ENOSYS)
  64                 return;
  65
  66 -       ret = thermal_zone_get_temp(tz, &temp);
  67         if (ret) {
  68                 if (ret != -EAGAIN)
  69                         dev_warn(&tz->device,
  70 @@ -783,10 +787,16 @@ emul_temp_store(struct device *dev, struct device_attribute *attr,
  71         if (kstrtoul(buf, 10, &temperature))
  72                 return -EINVAL;
  73
  74 -       if (!tz->ops->set_emul_temp) {
  75 +       if (tz->ops->set_emul_temp)
  76 +               ret = tz->ops->set_emul_temp(tz, temperature);
  77 +       else
  78 +               ret = -ENOSYS;
  79 +
  80 +       if (ret == -ENOSYS) {
  81                 mutex_lock(&tz->lock);
  82                 tz->emul_temperature = temperature;
  83                 mutex_unlock(&tz->lock);
  84 +               ret = 0;
  85         } else {
  86                 ret = tz->ops->set_emul_temp(tz, temperature);
  87         }
  88 --
  89 1.7.10.4
  90